Dental Asia Nov/Dec 2018

Clinical Feature DENTAL ASIA NOVEMBER / DECEMBER 2018 32 Examining Non-Carious Tooth Surface Loss By Dr. Christopher C.K. Ho , Specialist Prosthodontist Dr. Christopher C.K. Ho shares his experƟse on the cause, diagnosis and prevenƟon of tooth wear. N on-carious tooth surface loss is a normal physiological p r o c e s s t h a t o c c u r s t hroughou t one ’ s l i f e . However, it can often become a problem affecting function, aesthetics or may even cause pain. This loss of tooth structure or wear is often commonly termed abrasion, attrition, erosion and abfraction. Oftentimes, wear can be attributed to a complex combination of factors, making it difficult to identify a single cause. Therefore, diagnosis, prevention and treatment are based on the multifactorial causes of tooth surface loss. Causes Knowledge of the aetiology is important in preventing further lesions and ceasing the progression of lesions present. In addition, treatment will be ineffective in the long term unless the aetiological factors are eliminated. The following paragraphs discuss some of the causes: 1. Congenital abnormalities Amelogensis and dentinogenesis imperfect are congenital abnormalities that cause regressive changes in teeth and extensive tooth wear resulting from normal function. 2. Attrition It is described as the loss of tooth structure or restoration caused by mastication or contact between occluding or interproximal surfaces. It primarily affects occlusal or incisal surfaces, but slight loss can occur at the contact points. This type of tooth wear is significant in patients with “primitive diets” like the aboriginal population that tend to have a high quantity of dietary abrasives (Molnar et al, 1983). However, the most common cause of attrition is most likely due to parafunctional activity such as bruxism (Fig. 1) (Smith BGN, 1989 and Dahl et al, 1975). Fig. 1: Severe attrition on a 54-year-old patient with extreme wear due to bruxism. 3. Abrasion It is described as the loss of tooth substance or restorations caused by factors other than tooth contact. For example, rubbing of pipes, hairclips, musical instrument mouthpieces and excessive tooth picking could cause abrasion. The most common cause is incorrect or over-vigorous tooth brushing (Fig. 2). 4. Erosion This is the progressive loss of dental tissue by chemical means, excluding bacterial action. Acid is the most common cause of erosion that demineralises the inorganic matrix of teeth. a. Dietary erosion may occur from food and beverages such as fruit juices and soft drinks, which are highly acidic. The potential for erosive damages by these beverages are not well understood by the public. Another source of dietary acids are orallyadministered drugs like chewable vitamin C tablets, aspirin, iron t o n i c s a n d r e p l a c eme n t HC l (Hydrochloric acid) used by patients w i t h g a s t r i c a c h l o r h y d r i a (absence of HCl in the stomach) ( L e v i t h e t a l , 1 9 9 4 ) . A l s o , w i n e t a s t e r s o f t e n p r e s e n t significant erosion due to the constant erosive effects of the low pH found in wine. b. Regurgitation erosion is the reflux of gastric contents to the mouth. This is highly acidic (pH 2) and erosive. Repeatedepisodesmaybecome problematic. b.1. Involuntary regurgitation or gaestroesophageal reflux can occur due to hiatus hernia or as a consequenceof pregnancyor chronic alcoholism. b.2. Voluntary regurgitation is usually associated with an underlying psychologicalproblem. Eating disorders commonly associated are Fig. 2: Toothbrush abrasion lesions evident from over aggressive toothbrushing.